paul ryan, the vice presidential nominee preparing for his own debate avoided giving details much the tax plan even when pressed. >> haven't given me the math. >> i don't have the -- it would take me too long to go through all of the math. >> reporter: the president is in nevada at any time for what insiders call three days of debate camp at a resort outside of las vegas. they too are trying to lower expectations and believe the count that the romney campaign is convinced debates are about moments. >> the idea that i'm anti-immigrant is repulsive. >> reporter: and romney will come armed with several one-liners. >> they've been 3r5ing zingers and lines for months. i'm sure a bunch of clever lines but that's not what the american people are looking for. >> reporter: the president is being coached to be crisper, shorten his answers and a former democratic candidate says he needs to avoid being irritable. >> he's got to relax. he's got to show it and show a little sense of humor. he's got to show why he's likable. >> reporter: the debate is set for 90 minutes on wednesday night. it's all on d